package com.image.filter1;

import java.awt.Graphics2D;
import java.awt.color.ColorSpace;
import java.awt.geom.AffineTransform;
import java.awt.image.AffineTransformOp;
import java.awt.image.BufferedImage;
import java.awt.image.ColorConvertOp;
import java.awt.image.ColorModel;
import java.awt.image.MemoryImageSource;
import java.awt.image.PixelGrabber;

public class ImageFilter {
 private BufferedImage image;

 private int iw, ih;

 private int[] pixels;

 public ImageFilter(BufferedImage image) {
  this.image = image;
  iw = image.getWidth();
  ih = image.getHeight();
  pixels = new int[iw * ih];
 }

 /** 图像二值化 */
 public BufferedImage changeGrey() {
  PixelGrabber pg = new PixelGrabber(image.getSource(), 0, 0, iw, ih, pixels, 0, iw);
  try {
   pg.grabPixels();
  } catch (InterruptedException e) {
   e.printStackTrace();
  }
  // 设定二值化的域值，默认值为100
  int grey = 100;
  // 对图像进行二值化处理，Alpha值保持不变
  ColorModel cm = ColorModel.getRGBdefault();
  for (int i = 0; i < iw * ih; i++) {
   int red, green, blue;
   int alpha = cm.getAlpha(pixels[i]);
   if (cm.getRed(pixels[i]) > grey) {
    red = 255;
   } else {
    red = 0;
   }

   if (cm.getGreen(pixels[i]) > grey) {
    green = 255;
   } else {
    green = 0;
   }

   if (cm.getBlue(pixels[i]) > grey) {
    blue = 255;
   } else {
    blue = 0;
   }

   pixels[i] = alpha << 24 | red << 16 | green << 8 | blue;
  }
  // 将数组中的象素产生一个图像
  return ImageIOHelper.imageProducerToBufferedImage(new MemoryImageSource(iw, ih, pixels, 0, iw));
 }

 /** 提升清晰度,进行锐化 */
 public BufferedImage sharp() {
  PixelGrabber pg = new PixelGrabber(image.getSource(), 0, 0, iw, ih, pixels, 0, iw);
  try {
   pg.grabPixels();
  } catch (InterruptedException e) {
   e.printStackTrace();
  }

  // 象素的中间变量
  int tempPixels[] = new int[iw * ih];
  for (int i = 0; i < iw * ih; i++) {
   tempPixels[i] = pixels[i];
  }
  // 对图像进行尖锐化处理，Alpha值保持不变
  ColorModel cm = ColorModel.getRGBdefault();
  for (int i = 1; i < ih - 1; i++) {
   for (int j = 1; j < iw - 1; j++) {
    int alpha = cm.getAlpha(pixels[i * iw + j]);

    // 对图像进行尖锐化
    int red6 = cm.getRed(pixels[i * iw + j + 1]);
    int red5 = cm.getRed(pixels[i * iw + j]);
    int red8 = cm.getRed(pixels[(i + 1) * iw + j]);
    int sharpRed = Math.abs(red6 - red5) + Math.abs(red8 - red5);

    int green5 = cm.getGreen(pixels[i * iw + j]);
    int green6 = cm.getGreen(pixels[i * iw + j + 1]);
    int green8 = cm.getGreen(pixels[(i + 1) * iw + j]);
    int sharpGreen = Math.abs(green6 - green5) + Math.abs(green8 - green5);

    int blue5 = cm.getBlue(pixels[i * iw + j]);
    int blue6 = cm.getBlue(pixels[i * iw + j + 1]);
    int blue8 = cm.getBlue(pixels[(i + 1) * iw + j]);
    int sharpBlue = Math.abs(blue6 - blue5) + Math.abs(blue8 - blue5);

    if (sharpRed > 255) {
     sharpRed = 255;
    }
    if (sharpGreen > 255) {
     sharpGreen = 255;
    }
    if (sharpBlue > 255) {
     sharpBlue = 255;
    }

    tempPixels[i * iw + j] = alpha << 24 | sharpRed << 16 | sharpGreen << 8 | sharpBlue;
   }
  }

  // 将数组中的象素产生一个图像
  return ImageIOHelper.imageProducerToBufferedImage(new MemoryImageSource(iw, ih, tempPixels, 0, iw));
 }

 /** 中值滤波 */
 public BufferedImage median() {
  PixelGrabber pg = new PixelGrabber(image.getSource(), 0, 0, iw, ih, pixels, 0, iw);
  try {
   pg.grabPixels();
  } catch (InterruptedException e) {
   e.printStackTrace();
  }
  // 对图像进行中值滤波，Alpha值保持不变
  ColorModel cm = ColorModel.getRGBdefault();
  for (int i = 1; i < ih - 1; i++) {
   for (int j = 1; j < iw - 1; j++) {
    int red, green, blue;
    int alpha = cm.getAlpha(pixels[i * iw + j]);

    // int red2 = cm.getRed(pixels[(i - 1) * iw + j]);
    int red4 = cm.getRed(pixels[i * iw + j - 1]);
    int red5 = cm.getRed(pixels[i * iw + j]);
    int red6 = cm.getRed(pixels[i * iw + j + 1]);
    // int red8 = cm.getRed(pixels[(i + 1) * iw + j]);

    // 水平方向进行中值滤波
    if (red4 >= red5) {
     if (red5 >= red6) {
      red = red5;
     } else {
      if (red4 >= red6) {
       red = red6;
      } else {
       red = red4;
      }
     }
    } else {
     if (red4 > red6) {
      red = red4;
     } else {
      if (red5 > red6) {
       red = red6;
      } else {
       red = red5;
      }
     }
    }

    // int green2 = cm.getGreen(pixels[(i - 1) * iw + j]);
    int green4 = cm.getGreen(pixels[i * iw + j - 1]);
    int green5 = cm.getGreen(pixels[i * iw + j]);
    int green6 = cm.getGreen(pixels[i * iw + j + 1]);
    // int green8 = cm.getGreen(pixels[(i + 1) * iw + j]);

    // 水平方向进行中值滤波
    if (green4 >= green5) {
     if (green5 >= green6) {
      green = green5;
     } else {
      if (green4 >= green6) {
       green = green6;
      } else {
       green = green4;
      }
     }
    } else {
     if (green4 > green6) {
      green = green4;
     } else {
      if (green5 > green6) {
       green = green6;
      } else {
       green = green5;
      }
     }
    }

    // int blue2 = cm.getBlue(pixels[(i - 1) * iw + j]);
    int blue4 = cm.getBlue(pixels[i * iw + j - 1]);
    int blue5 = cm.getBlue(pixels[i * iw + j]);
    int blue6 = cm.getBlue(pixels[i * iw + j + 1]);
    // int blue8 = cm.getBlue(pixels[(i + 1) * iw + j]);

    // 水平方向进行中值滤波
    if (blue4 >= blue5) {
     if (blue5 >= blue6) {
      blue = blue5;
     } else {
      if (blue4 >= blue6) {
       blue = blue6;
      } else {
       blue = blue4;
      }
     }
    } else {
     if (blue4 > blue6) {
      blue = blue4;
     } else {
      if (blue5 > blue6) {
       blue = blue6;
      } else {
       blue = blue5;
      }
     }
    }
    pixels[i * iw + j] = alpha << 24 | red << 16 | green << 8 | blue;
   }
  }

  // 将数组中的象素产生一个图像
  return ImageIOHelper.imageProducerToBufferedImage(new MemoryImageSource(iw, ih, pixels, 0, iw));
 }

 /** 线性灰度变换 */
 public BufferedImage lineGrey() {
  PixelGrabber pg = new PixelGrabber(image.getSource(), 0, 0, iw, ih, pixels, 0, iw);
  try {
   pg.grabPixels();
  } catch (InterruptedException e) {
   e.printStackTrace();
  }
  // 对图像进行进行线性拉伸，Alpha值保持不变
  ColorModel cm = ColorModel.getRGBdefault();
  for (int i = 0; i < iw * ih; i++) {
   int alpha = cm.getAlpha(pixels[i]);
   int red = cm.getRed(pixels[i]);
   int green = cm.getGreen(pixels[i]);
   int blue = cm.getBlue(pixels[i]);

   // 增加了图像的亮度
   red = (int) (1.1 * red + 30);
   green = (int) (1.1 * green + 30);
   blue = (int) (1.1 * blue + 30);
   if (red >= 255) {
    red = 255;
   }
   if (green >= 255) {
    green = 255;
   }
   if (blue >= 255) {
    blue = 255;
   }
   pixels[i] = alpha << 24 | red << 16 | green << 8 | blue;
  }

  // 将数组中的象素产生一个图像

  return ImageIOHelper.imageProducerToBufferedImage(new MemoryImageSource(iw, ih, pixels, 0, iw));
 }

 /** 转换为黑白灰度图 */
 public BufferedImage grayFilter() {
  ColorSpace cs = ColorSpace.getInstance(ColorSpace.CS_GRAY);
  ColorConvertOp op = new ColorConvertOp(cs, null);
  return op.filter(image, null);
 }

 /** 平滑缩放 */
 public BufferedImage scaling(double s) {
  AffineTransform tx = new AffineTransform();
  tx.scale(s, s);
  AffineTransformOp op = new AffineTransformOp(tx, AffineTransformOp.TYPE_BILINEAR);
  return op.filter(image, null);
 }

 public BufferedImage scale(Float s) {
  int srcW = image.getWidth();
  int srcH = image.getHeight();
  int newW = Math.round(srcW * s);
  int newH = Math.round(srcH * s);
  // 先做水平方向上的伸缩变换
  BufferedImage tmp=new BufferedImage(newW, newH, image.getType()); 
  Graphics2D g= tmp.createGraphics(); 
  for (int x = 0; x < newW; x++) {
   g.setClip(x, 0, 1, srcH);
   // 按比例放缩
   g.drawImage(image, x - x * srcW / newW, 0, null);
  }

  // 再做垂直方向上的伸缩变换
  BufferedImage dst = new BufferedImage(newW, newH, image.getType()); 
  g = dst.createGraphics();
  for (int y = 0; y < newH; y++) {
   g.setClip(0, y, newW, 1);
   // 按比例放缩
   g.drawImage(tmp, 0, y - y * srcH / newH, null);
  }
  return dst;
 }

}
